This invention relates generally to over the road tractor-trailers and more particularly to a device that provides a warning when the driver leaves the cab without having set the parking brake.
When a large over the road tractor-trailer is parked and the driver leaves the cab even temporarily, it is essential that the parking brake be securely set. Otherwise, the tractor-trailer can accidentally begin rolling, and this can damage or even destroy the tractor-trailer and anything in its path. There have been instances of significant property damage and severe personal injury resulting from the failure of the truck driver to set the parking brake.
Accordingly, there is a need for some way to make certain that the tractor parking brake is set whenever the operator leaves the cab. The present invention is directed to a warning device that generates a warning signal whenever the operator's seat is vacant and the parking brake is at the same time in its released position. Consequently, the driver is immediately alerted to the unsafe condition and can set the parking brake before the tractor-trailer has had a chance to begin rolling. The warning system is automatically deactivated whenever the driver's seat is occupied and also whenever the parking brake is set. Thus, the warning signal is given only when there is a potentially unsafe situation created by the parking brake being in the release position simultaneously with the driver vacating the operator's seat in the cab of the tractor.